1. Field of the Invention
This invention relates to a tool for installing and removing power transmission belts from fixed center pulleys. It is particularly directed to continuous belts having an inner multi-rib construction adapted to engage pulleys which have a matching set of V-grooves. A typical v-ribbed belt system is shown, for example in Fisher et al., U.S. Pat. No. 3,951,006. In this system, pulleys are coupled to the engine drive shaft and to such accessory drives as the alternator, water pump, power steering pump, or air conditioning compressor. The belt is operated over the drive shaft pulley and drives the accessories provided in the system. Although the above referenced patent also utilizes a tensioner applied to the outer surface of the belt, such a device is not always required. The term xe2x80x9cmulti-ribxe2x80x9d is understood to mean a belt having its inner drive surface formed of a plurality of V-shaped or trapezoidal members shaped driving members designed to inter-fit with associated pulley grooves.
Tools of this type are necessary to install the belt over the various pulleys in the system, and also to remove the belt, and must be capable of accomplishing this with minimum effort and damage to the belt. The tool may also be used to test special accessory drive configurations, such as during a routine hot test after engine assembly. For example, it may be desired to test a water pump, in which case only the water pump is installed and the tool is applied only to the pulley which is attached to this pump.
2. Prior Art Statement
It is been known to utilize simple hand tools for the purpose of installing a conventional power transmission V-belt having a single trapezoidal drive section. This is done by the use of a wedging tool such as shown in Engard et al., U.S. Pat. No. 2,470,810 and Hawkins, U.S. Pat. No. 2,621,529. A variation of these wedging devices is shown in Simmons et al., U.S. Pat. No. 2,505,216 wherein a tool having a curved cam surface is used to permit the single section belt to slide over this surface onto the pulley.
It is an entirely different problem to install a multi-rib belt, however, and one such device is shown in Winninger, et al., U.S. Pat. No. 6,033,331, wherein a similar wedging tool is used to position a multi-rib belt onto a pulley. In all of the above patents the tool is not secured to any member of the drive system, and must be operated without any support, making the operation more difficult.
The present invention is an improvement over the prior art and provides for a tool which has a principal member to be mounted directly on one of the accessory drive pulleys and secured thereto, thereby providing a secure support for the tool. This makes it easier to operate and to control the belt. The principal member has a plurality of circular openings for insertion of either an installing device which allows the belt to be stretched and installed on the selected pulley; or a removal device which enables a belt to be stretched and removed from the pulley. The principal member also comprises a control member, such as a pair of handles, which are used to rotate and manipulate the principal member into the desired installing and removal positions of the belt. To install the belt around the pulleys, the installing device is first inserted into one of the circular openings by utilizing an integral pin on the device. This is inserted into whichever of the openings that provides clearance in the drive system. At the same time, other members will lock the installing tool in place so that it will not fall out. The principal member has an external cylindrical shaft which is inserted into the inner circular opening of the pulley. In order to lock the cylindrical shaft in place within the pulley, a bolt in the principal member is tightened, this bolt being connected via a wedging nut to locking members within the surface of the principal member. This rotation expands the locking members to lock them in place within the pulley. The belt is placed loosely around the other pulleys in the drive, then around the installing tool surface, which is designed with a curved cam configuration. At this point the belt is located outwardly of the pulley flanges.
The handles are rotated and manipulated so that the belt is slid over the ramp surface of the installing tool and onto the belt-engaging surface of the pulley. The ramp provides support to the inner surface of the belt, while simultaneously wrapping the belt around the installation pulley. This insures inter-engagement of the ribs of the belt and the grooves of the pulley. The tool is then disengaged by loosening the bolt to release the locking members which will then no longer be locked within the inner pulley surface. The power transmission system is then in condition for operation.
The removal of the belt is accomplished by placing the belt removal attachment in the same manner as the installing device. This device also has an integral cylindrical pin which is inserted into one of the circular openings in the principal member. This device has a belt-supporting surface which is similar to that of the installing device, with a concave surface acting as a cam or ramp. The configuration of this surface is slightly different than that of the installing device, in order to facilitate removal of the belt. To remove the belt, the principal member is again placed within the pulley, and the bolt is tightened to lock the principal member with the pulley as before. The principal member is rotated, using the handles, forcing the cam surface under the belt, so that the belt is twisted and stretched during this manipulation and the belt is slid from the pulley onto the removal device, thus removing it from pulley contact.
It is a principal object of this invention to provide a tool for installing and removing a power transmission belt without damaging the belt or other components.
It is a further object to operate the tool in a simple manner without other tools.
It is a further object to provide the tool with a secure mounting base to accomplish its purpose.
It is another object to provide the tool with separate installation and removal devices which may be locked in place.
These and other objects of the invention will become apparent from viewing the principal embodiment shown and described herein.